From 7eeec07e9bd908ba770efa0518fc83c9bf2b7002 Mon Sep 17 00:00:00 2001 From: Artem Blagodarenko Date: Tue, 27 Aug 2013 17:53:57 +0400 Subject: [PATCH] LUDOC-98 mgs: Document new lctl replace_nids feature This is to track documentation for the "lctl replace_nids" feature in LU-1430. Xyratex-bug-id: MRP-397 Signed-off-by: Artem Blagodarenko Change-Id: I3f5de27b51fd2cdb467f6ca5c0c308bd8c72f5b9 Reviewed-on: http://review.whamcloud.com/7459 Tested-by: Hudson Reviewed-by: Linda Bebernes Reviewed-by: Andreas Dilger --- LustreMaintenance.xml | 61 ++++++++++++++++++--------------------------------- 1 file changed, 21 insertions(+), 40 deletions(-) diff --git a/LustreMaintenance.xml b/LustreMaintenance.xml index 3b2a844..fc43567 100644 --- a/LustreMaintenance.xml +++ b/LustreMaintenance.xml @@ -199,27 +199,29 @@ Regenerating Lustre Configuration Logs
<indexterm><primary>maintenance</primary><secondary>changing a NID</secondary></indexterm> Changing a Server NID - If you need to change the NID on the MDT or an OST, run the writeconf command to erase Lustre configuration information (including server NIDs), and then re-generate the system configuration using updated server NIDs. + In Lustre 2.3 or earlier, the tunefs.lustre --writeconf command is used to rewrite all of the configuration files. + If you need to change the NID on the MDT or OST, a new replace_nids command was added in Lustre 2.4 to simplify this process. + The replace_nids command differs from tunefs.lustre --writeconf in that it does not erase the entire configuration log, precluding the need the need to execute the writeconf command on all servers and re-specify all permanent parameter settings. However, the writeconf command can still be used if desired. Change a server NID in these situations: - New server hardware is added to the file system, and the MDS or an OSS is being moved to the new machine + New server hardware is added to the file system, and the MDS or an OSS is being moved to the new machine. - New network card is installed in the server + New network card is installed in the server. - You want to reassign IP addresses + You want to reassign IP addresses. To change a server NID: - Update the LNET configuration in the /etc/modprobe.d/lustre.conf file so the list of server NIDs (lctl list_nids) is correct. + Update the LNET configuration in the /etc/modprobe.conf file so the list of server NIDs is correct. Use lctl list_nids to view the list of server NIDS. The lctl list_nids command indicates which network(s) are configured to work with Lustre. - Shut down the file system in this order. + Shut down the file system in this order: Unmount the clients. @@ -232,43 +234,22 @@ Changing a Server NID + + If the MGS and MDS share a partition, start the MGS only: + mount -t lustre MDT partition -o nosvc mount_point + - Run the writeconf command on all servers. - Run writeconf on the MDT first, and then the OSTs. - - - On the MDT, run: - mdt# tunefs.lustre --writeconf /dev/mdt_device - - - On each OST, run: - ost# tunefs.lustre --writeconf /dev/ost_device - - - If the NID on the MGS was changed, communicate the new MGS location to each server. Run: - tunefs.lustre --erase-param --mgsnode=new_nid(s) --writeconf /dev/device - - - - - Restart the file system in this order. - - - Mount the MGS (or the combined MGS/MDT). - - - Mount the MDT. - - - Mount the OSTs. - - - Mount the clients. - - + Run the replace_nids command on the MGS: + lctl replace_nids devicename nid1[,nid2,nid3 ...] + where devicename is the Lustre target name, e.g. myfs-OST0013 + + If the MGS and MDS share a partition, stop the MGS: + umount mount_point + - After the writeconf command is run, the configuration logs are re-generated as servers restart, and server NIDs in the updated list_nids file are used. + The replace_nids command also cleans all old, invalidated records out of the configuration log, while preserving all other current settings. + The previous configuration log is backed up on the MGS disk with the suffix '.bak'.
<indexterm><primary>maintenance</primary><secondary>adding an MDT</secondary></indexterm>Adding a new MDT to a Lustre file system -- 1.8.3.1